Washing or cleaning agents resp. cosmetic agents usually contain scents that impart a pleasant odor to the agents. The scents usually mask the odor of the other ingredients, producing a positive odor impression on the consumer.
In the sector of washing agents in particular, scents are important constituents of the composition, since the laundry should have a pleasant and, if possible, also fresh smell both when wet and when dry. A fundamental problem faced in the utilization of scents is that these are more or less volatile substances, but that a long-lasting scent effect is nevertheless desirable. The desired persistence of the scent impression is very difficult to achieve especially with those fragrances that represent the flesh and light notes of the perfume, and that evaporate particularly quickly because of their high vapor pressure.
Delayed scent release can occur, for example, thanks to carrier-bound use of scents. A carrier-bound precursor form of a scent is also known as a “pro-fragrance” or scent storage substance. In this connection, International Patent Application WO 2007/087977 discloses the use of 1-aza-3,7-dioxabicyclo[3.3.0]octane compounds as scent storage substances for delayed release of scent aldehydes and scent ketones by hydrolysis. An alternative possibility for delayed release of scents is represented by the use of so-called photoactivatable substances as scent storage substances. The action of sunlight or another electromagnetic radiation source of a specific wavelength induces breakage of a covalent bond in the scent storage substance molecule, thereby releasing a scent.
U.S. Pat. No. 6,949,680 discloses the use of specific phenyl ketones or pyridyl ketones as photoactivatable substances that, in a photochemical fragmentation, release a terminal alkene as an active substance in the presence of light. The aforesaid active substance possesses, for example, a scent-imparting or antimicrobial activity that is first delayed by the photochemically induced decomposition, and over a longer period of time is released on a specific surface. WO 2009/118219 A1 discloses photoactivatable substances that permit the release of cyclic terpenes or cyclic terpenoids.
The object of the present invention was to provide photoactivatable substances constituting scent storage substances, which permit the delayed release of fragrance ketones, in particular damascones.
This object is achieved by a ketone of the general formula (I)
in which    R denotes a hydrocarbon residue that comprises at least one C═O group,    R1 denotes a linear or branched, substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, in particular a methyl group,    R2, R3, R4, R5, R6, and R7, mutually independently, denote hydrogen, a halogen atom, NO2, a linear or branched, substituted or unsubstituted alkoxy group having 1 to 15 carbon atoms or a linear or branched, substituted or unsubstituted alkyl group having 1 to 15 carbon atoms.
Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.